Canister



Nov. 23, 1943.

c. w. PUNTONET AL 2,334,840

GANISTER Filed June 29, 1940 2 Sheets-Sheet l INVENTORS.

A TTORNE X CHARLES m PUNToM Nov. 23, 1943. c. w. PUNTON ETAL 2,334,840

CANI STER Filed June 29', 1940 2 Sheets-Sheet 2 INVENTORS. CHA RL as w. PUNrou A T TORNEX Patented Nov. 23, 1943 TY 'oFFicEQ-fl GANISTER Charles W. Puritan, Penn Township,

County, and William P assignors torMine Pittsburgh, Pa.

. Allegheny Yant, Pittsburgh, Pa.,

Safety Appliances Company,

Application June 29, 1940, Serial No. 343,236 H v routes, (o1. 1ss+ i4 if This invention relates to animprovementin the. construction or assembly of an air purifying canister and more particularly to a method of manufacture and the construction of acanister which can be made of relatively thin sheet metal material, which isrigidand possesses'suificient strength for all purposes .for which the canister may be used, and which possesses advantages not provided in prior canister manufactures: I In breathing apparatus of thepersonal protection type,.a canister is included in the apparatus and contains materials which remove contaminants and toxic substances from air and makes it suitable for respiration. Generally, the canister contains a mechanical. filter which. is made of some fibrous material and 'isadaptable for removing smokes, dusts and. fumes, and, in addie ticn, itcontains appropriate materials for'removaing substances by absorption or chemical reaction. Because thecanister is borne by the wearer and because of certainconditions existing inthe use of the type of apparatus considered, it is necessary that any construction of th lcanister used must be as compact as possible and yet provide adequate space for the. purifying materials;

Furthermore, because of the small'servicfe time of the purifying materials contained ina-canister and inability to arrange forv facilitie for replenishing the materials, it is necessary that the canister construction be comparatively inexpensive and be adequately strong and rigid while providing sufficient space for accommodating the materials.

It is among the objects of this invention to provide'a canister construction and a method .of

manufacture in whichthe canisterjisadaptable i i to ready fabricationand is sufficiently sturdy, inexpensive and simple in construction and can be made of relatively thin sheet m-etal mat'erial and which can be made to accommodate mate rials necessary for providing a canister having adequate service time for practical purposes.

Further objects of this invention will become apparent from a description-of one embodimentof my invention. of a noveiycanister' construction and that part of the invention relatingsto the method ofmanufactur-ing; 4' q l Inthedrawingsz- Fig. l is a sectional plan viewgxofthe embodiement taken along the line i- -l-of Fig-. -2;';-

Fig. 2 is a sectional view taken along-the line 22 of Fig. l;

Fig. 3 is aplan view of the sameeinbodiment-y Fig. his a detail .view partly in :jsection illus v trating an assembly of a connection which forms apart ofthe embodimeiitg'and 3 i a I Fig. 5 is an enlarged fragmentary sectional view taken along-line,22of Fig.1.. I 1

The type of canister selectedfor describingthis invention has been used heretoforeand contains 1 an air ,passage through a' housing and in which is cdisposed the materials selected forpuriiying air when traveling through thepassage, For the purpose of efficiency in operation, th air enters amopeningiinthe bottom of the canister. and is then deflected laterally and is constrained to pass through a mechanical filter extending along the length of the housingbut inside thereof, and after passingthrough the; filter, the air passes through. chemical materials which react with-or sorbthe contaminants or toxic substances' and complete the treatment of the air-and, render it suitableqfor respiration. A centraltube collects the treatedair andto'whichan outlet connection is attached. This connected is connected'to the face-piece bymeans of a breathing tube and the whole canister is supported'from the housing. \In view of the operation of the canister, the central tube in collecting the treated air serves somewhat asareservoir and its volumetric capacity is of muchimpo'rtance,

Itis atf eatureof this inventiontoprovide tains-a. central tube 2 represented asbeing. oblong in shape transversely of the tube, that is, having one maj or dimension much greater than the other and whichfhas sufficient volumetric Tcapacityfor storingthe necessary amounts of an during the cycles in the operation of the apparatus. This shape of the tube is preferred for support purposes but the invention is notglimiteol thereto. Theitube is usually disposed centrallyof the sur -i rounding functioning parts making up the cams; tenfj It is to be recognized that while in this description thetube is referred to as a central tube,

this connotationis not 'to be conside ed a limitation; because the tube can be disposed, in any other manner relative to the othen parts without departing from thescopeofthis invention. .The tube isjmade of thin sheet metal as ,well. as are other elements making up. the canister assembly andj-the tube is of a perforated. wallsection for the-,most part toreceive the air afterbeing treated, and-"for. some purposes, it isnecessary. to] furtherrestrict the perforations by applying athinfabric material onthe outside of the tube since it} has been found in manufactureto Joe advantageous to use perforated material ofasize I having openings larger than necessary and then r V -provided in shaping the tube.

" outlet connection 6.

closes the. perforated section andi attached to the body of the tube b'jmeahs of an adhesive tape 4. p

The upper end the perforated portion can be made'ofon'e piece of material so thatthe central tube; hereinafter identified as"2, is composed of the whole duct extending from the upper portion 2a to andincluding the lower portion 212. The upper end 2a has attached an intermediate metal connector or upper lateral extension 7 having a flange J 5a. abutting the surface of the tube and whichcan" be fast'enedby'means of soldering or any of'the' other expedients for attaching'thin metal surtherewith and The outer extent of this extension contains a depending flange '5b which abuts a similar surface of an The outlet connection" 5 to be connected to a breathing apparatus (not shown) contains at its receiving end an outer faces. or it can be made integral depending flange Ea to which anfinnerperforated' wallor housing member] is'connected.

The-lower extentof thebreathing of the tube proper and closing off itsop'ening at this extent. Supported thereto is-a lower =lat- 'eral'extension 9- having portions ea upstruck from: a flat surface and in a manner to accommodate thecup 8 soas' toposition the cup and thetube inproper relation to the member 9. This farrangement allows some tole rance-lin manufacturebut "modifications can be made readily as by extending the .upstruck portions to serve the, same purpose asIthe cup-B. 'This 'member S has an outer flangeflb to which thev inner wall '5 is attached at its lower, extremity,

This wallj l defines an inner chamberJZU for accommodating and confining the chemical materials c thatare disposed'in the pathof air portion or the tube 2 repre-' sented as 2a is illustrated in the drawings, Figs; '2 and 5, as being made of a piece, separate from v the perforated section andjoinedbyanyisuitablemeans, but, as is obvious, thisend portion and tube 2b has a' cupa resiliently engaging the lower portion constrict the openings by use 'ofrfabric' material. The fabric is represented as 3 and completely enor discwhich covers the opening I? represented. v V

by a valve as a series of smalljopenings jfia, Fig. 1. In:

order to'space the base member 'i5 from the. g under surface of the lower lateral extension 9' and to support the functioning parts of they canister from the housing or carriagemember" .13, separate upstanding extents l8 integral with; the base niemberengage the surface of the mem- 'ber *9 andjspacethe'base member therefrom-1' These eirt'ents'are so made-that-an outside suriace i8a engages the flange surface 9%; inwardly 70f the-section illustratedin Fig. 2 so as to hold a the member 9 in place relativev to housing mern-'- ber I3, and they are much smaller at the upper extremityv than at the base in order to provide anadequate passage from the inlet opening lfif to the space provided between the innerand to be: treated- A mechanical filter means 18 which may be 'a' fibrous" material suitably im pregnated 'to'remove dusts and smokes and solid particles suspended in the air-is wrapped around theo'uter surface of the wallin'some fashion as in a spiral manner and is held thereto by means'of resilient clips II and I2 at each ,end

of .the filter. An outer housing or carriage member l3 containing corrugations or outwardly extending bulgesHa provided in order to .grip a V fabric harness is connected. to. the central tube and in spaced relationito thebutermost surface of *the vjfilter ill by means of a metal; connector H which engages" a-surface oftthe outlet conth'e outei" housing l3. and the connector I4 that a' 'suitable connectionis' provided and itiallows quick frer'noval oi the; outer "housinjg' from the filtering partsof" an operative air purifying canister, should itbecomenecessary The lower. 7; end of the housing is connected to-a'base mem f 'ber: liwhich extends outwardlywa sufficient distance to dispose the lower extent ofthe housing in alignment with the iuppei extent; and it is attached thereto by crimping as usedin connectm th: u r len oi -i his a m mbe .7 "contains an inlet opening 1B which is" controlled outer housing members 1 and 53; As is obvious;

this. space between the housing members'should be suificient to accommodate the mechanical filter H3 and also provide a space between the outer surface of the filter and the surface of I i the housing l3: toallow free passage of :air over the entire operative surface'of the" filter and limit the resistance to movement of air as much as possible. I 1 r In the operation of this canister, air is drawn through the inlet opening is during inhalation;

of the wearer and by: the force of suction the air "passes between the base member l5 and the 1 lower lateral extension 9' to the space betweenthe filter h] 'and the outer housing l3. The air then passes through the mechanical filter and thechemioal materials designated as 28 and. then intothe space provided by the central tube 2; From here the air then passes through the outlet connection 6 and into a" breathing 'tubei connected a'facek a (not shown) and to. which is piece Worn by the user.

In the attachment of provides a suiiiciently'strongconnection for' engaging the-separated parts which are to be at:

tached, except that-the attachment ofthe outer basemember l5 is by crimpingand it isap'p'ar'e nection 6 and to which the central-tube isjcon 1 :nected through the lateral extension? It has been;foun d that by crimping the edges" of both 7 housing' 13' to the-central tube is by crimping V to allow ready removal of the housing if ne'cesv sary.: The attachment of the housing I3to the ent that these two members could be made' of a single piece although for manufacturing it is i' I preferred that theybe made as represented; It-- is apparent from'thisdescription that the funotioning of the canister as'an operative unit does not require the outer housing l3 asg aymeansof 7 7' support and all the necessary partsfarefsupp'ortedeither directly or indirectly from the central: tube 2. By thisarrangemena-in theevent that l .1 it becomes necessary toremovethecarriage-or. outer housing member 13, the'canister can bef} carried bymeansofthe' outlet connection which 7 in turnisattachedto the central tube and-from" which the parts supporting the purifying--ma" i terialsare supportedp Theresilient attachment of the central tube to thelower'lateral extension '9 bymeans of cup: Sallows for variations in the length of the tube "and in'the assembly sincefit 1 has been found that it is more practical to provide this member th'an extend the upstruckf 1 D ti0ns'9a "a sufl'icient distance to accommodate;

the variations that may occur;{'

Another; feature of this invention is ithat -thear' Q l1 composed of a thin rubber plate 5 the various flat surfaces "Ll or flanges of the several component members to"! acomparable surface of an abutting member; any-means offpermanent attachment'fcan be used, and'it has been found that s'oldering' itselt 1 easiest;

fabrication: of the canister isadaptable to a novelmethod of construction of" a canister and a descriptionof a preferredmethod' will dis-. close the;prin.ciple involved; 'thereof.- In-this method of manufacture-the central tube 2;. is made from a fiatperforatedsheet by suitable shaping and crimping; A fabric isi then applied to. theouter surface to restrict the openings to the desired extent and is fastened bytmeans of a suitable adhesive or tape; Toth-is tube. the intermediate member is'attachedand to which theoutlet connection has previously been attached. v The inner wall member 1- is then. connected to the flange surface of the outlet connecticn 6, and at this stage of assembly the chemical material. is then placed in the intermediate chamber -20 thus formed. The cup 8 and lower lateral extension Qarethen added to the central. tube and: the latter is attachedxto the lower'end-ofthe inner wa-ll'v l. )The mechanical filter H! is :then attached to the outer surface of. the inner wall! byresi-lient clips It and 12. The housing I-3 and. base member l5 are connectedtogether by .crim-pin'gpreliminary to their assembly. to thefilter unit-and then the unit is passed-thereinto and positioned onto the extents l8. The connector I4 is connected to the housing. 13 and soldered. tothe outlet conan a abutting "surface. engaging a surface of the tube and being connected the'reto, an. outlet con: nectionmember having a-surface engaging a surfaceof the lateralextension support member v and being; atta ehed thereto andhaving a passage 7 connected tothe passageof' thei central tube,,a

lower lateral extension member having a portion.

' ing members in which a filter can be positioned nection 6. It has been foundthat: if housing 13- l is. made a trifle shorter than requiredth-at the assembly willdistorttheconnector l4 and make it operative as" a spring member. This result is beneficial because it'actsas a means to place a slight. strain on the engagement of the con-. nector M with the outlet connection 5. andtpro vides a tight attachment of the lower member'- 9 tothe extents l8 and prevents any lateral.

movement ofany of the parts within the housing l3 which might prove destructive and which may occur byrough handling. It is apparent. that this series of steps in manufacture describe: one embodiment of the general sequence which: is to be followed, but it is recognized that other methods can be devised which will incorporate the general sequence developed. a a

From this description of our" invention, it is. to be observed, also, that the elements making. up the canister can be readily fabricated and by: reason of their construction and. arrangement provide ample rigidity and sturdi-ness: to a com-- plete: canister while providing thenecessary space for accommodating the passages and air purify-- ing. materials contained withinthe canister andlend themselves readilyto our method of manufacture. Furthermore, by the arrangement the joints formed by the engagement of the separated parts adapt themselvesreadily to any available practical process used for conneetingLsuch-parts; Other advantages are present whichare obvious from the above'description of the preferred em-' bodiment of our invention.

It is intended that this detailed description of the construction of the canister be for the pur-- pose of a full and complete description of the adaptation of our. invention to. one embodimentincorporating the; principle and modeof opera-.

tionof our invention andwithin the scope of the.

appended claims, and we desire to have it understood that the invention may be practicedrotherwise than as specifically illustrated and described.

We claim:

1. A rigid fabricated sheet metal canister comprising a central perforated tube and support member having a transverse oblong shape, an upper lateral extension support member having housing members.

2. A fabricated sheet metal canister comprising a perforated tube and support member having a transverse oblong shape, anupper lateral extension support member having an abutting surface engaging- .a surface of the tube and supportedtherefrom, an outlet connection having a surface engaging. and attached to a surface of: the lateral extension support member and having: an; inner transverse-dimension comparable to the width ofthe-tube, the tube, and outlet connection being disposed so that the tube-engagingportion of said lateral. extension member engagesthe walLof the outlet connection and the passage of the outlet connection is; in alignment with the: passage of the tube, a lower lateralfextension having aiportionupstruck to provide an upstanding receiving portion, an intermediate receptacle resiliently engaging the portion and receiving and closingoff the lower end of the tube and supported therefrom, an. inner perforated housing member engaging a surface of the outlet connection and the. lower lateral extension and fastened thereto. and: defining an air purifying material" compartment, an. outer carriage member having spaced corrugations and detachably supported and provide an airpassage across the surface of the filtermeans, said. carriage member including a bottom portion containing. an inlet opening and carrying upstanding spaced members; to engage the lower lateral extension member to space the" bottom portion from. the lower lateral'extension and provide a passageconnectingthe inlet open ing-to the perforate-dhousingmember.

3. A fabricated'sheet metal canister comprising" a perforated tube and support member having" a transverse oblong shape, an. upper lateral extension support member'havingan abutting surface engaging a. surface of the tube and supported therefrom, an. outlet connection having an undersurface engaging and attached to an outer surface of the lateral extension support member, the inner Wall surface of the connection defining a widtlrof passagesubstahtially that of the width of the tube, the tube and. outlet connection being disposed so that the tube-engaging 'portionof" said lateral extension member engages the inner wall ofthe-outlet connect on and the piss-age the outlet connectionis in a ignment with the passage of-thetube, a'lower lateral extension havinga portion upstruck toprovide an upstanding receiving portion, an intermediate receptacle resiliently engaging the portion and receiving and I closing off the"'lower"end of the tube andsup:

ported therefrom; an inner perforated housing member'engaging a surface of the outlet connection' and'the lower lateral extension and fastened thereto and defining an 'air purifying material compartment, suitable materials in the compartment, amechanical filtermeans attached to the surface of the inner housing, an "outer carriage 4'.'A fabricated sheet metal canister compris ing' a perforated tube and support member having' a transverse oblong shape, an upper lateral extension support member having an abutting surface engaging a surface of the tube and supported therefrom, an outlet'housing connection having an undersurface engagingand attached to an "outer surface of the latral extension support'member, the transverse dimension of'the inner wall of the outlet connection being of substantially-the same sizeas the greater dimenocesan shoulderja lateral extension member in theiewei end of the outlet connection provided centrally 1 with a restricted opening and having its marginal portion connected to the inside of said shoulder, a central perforated tube havingits upper end attached to the'lateral extension member 'in said opening, means closing the lower end of said tube, a bottom plate below the tube, an inner perforated wall member attached to the'outer edge of said flange and to said bottom plate for defining an air-purifying material compartment around the central tube, a filter positioned against the outer surface of'saidinner perforated wall member, a protective housing sur-' rounding the filterand spaced therefrom and provided with an air inlet, and a ring connecting the upper end of the housing to'the outsideof saidvshoulder to support the housingtherefromg Y 6. A fabricatedsheet metal canister comprising a tubular outlet connection member having at its lower end a' laterally extending flange, said flange having a downturned portion space'd'inwardly from its outer edge to form a continuous shoulder, a lateral'extension member in the lower end ofthe outlet connection provided centrally V with a restricted opening 'andhaving its marsion of the'tube, thetube-engaging portion of said lateraliextension member engaging the inner wall'surfa'ce of the outlet connection and the passage of the outlet connection being in align ment with theipassage of the tube, a lower lateral extension having a portion upstruckto-provide an upstanding receiving portion, an intermediate receptacle'resiliently engaging the portionand receiving and closing off the lower end of the tube and supported therefrom, an inner perforated housing member engaging a surface of, the outlet connection and the lower lateral extension and fastened thereto and defining an air purifying material compartment, suitable materials in the com artment; a mechanical filter: means attached to the surface of the inner,

housing; an outericarriage member having spaced corrugations in its side wall and having a surface attached to an outer surface of the outlet connection inspaced relation to the outermost surface of the filter'means, said carriage member including a bottom portion containingan inlet opening and carrying upstanding spaced membersto-engage the lower lateraljextension memher to prevent any lateral movement thereof and to space. the bottom portion from the lower lateral extension and provide a passage connecting theinlet opening to the passage above the filter means, andthe attachment of the carriage mem her being such as to produce strain on-the engaging parts of the canister and provide a rigid assembly. V v 5. A fabricated sheet metal canister comprising a tubular outlet-connection member havin atits lower end a laterallyextending' flange, said flange having a downturned portion spaced inwardly from its outer edge toform a continuous restricted oblong'opening and having a downginal portion connected to the inside of said shoulder, a central perforated tube having its upper end attached to the lateral extension member in said opening, a bottom plate below the tube, a cup mounted on the plate and resiliently gripping the-lower end of said tube to close it, an inner perforated wallmember'attachcd to the outer edge of said flang and to said bottom plate for defining-an air-purifying material compartment aroundthe central tube,-

a filter positioned against theoutersurface of said inner perforated'wall member, a protective hou ing surrounding the filter and spaced therefrom and provided with an'air inlet, and a ring connecting the upper end of the housing to the outside of said 'shoulder to support the housing therefrom. Y a

- 7. A fabricated sheet metal canister compris ing a tubular 'outlet connection member'having at its lower end a laterally extending flange, said flange having a downturned marginal portion and having a down-turned portion spacedinwardly therefrom to form a continuous'sho'ulden' a lateral extension member in the lower end of the outlet connection provided-centrally with a turned marginal portion connected to the inside of said shoulder, a central perforated tube'oblong in transverse section attachedat its upper end to the lateral extension member in said opening, means closing the lower end of said tube,

a bottom plate belowthe tube, an inner perfo-1 rated wall member attached to said down-turned marginal portion of said flange and to the edge of said bottom plate for defining an air-puri fying material compartment around the central tube, a filter positioned against the outer surface of said'inner perforated wall member, a

protective housing surrounding the filter and spaced therefrom and provided with an air in CHARLES W. PUNION.

WIILIAM P. YANT. 

